For a wide variety of applications, chairs are nowadays provided with features which provide enhanced comfort to the person using the chair. For illustration, office-type chairs are commonly utilized in modern working environments to provide an occupant with a level of comfort while performing certain tasks that require a person to be in a seated position for an extended period of time. One common configuration for such a chair includes a mobile chair base assembly to allow the chair to roll across a floor and a pedestal column supporting the superstructure of the chair. The superstructure may include components which enable the user to adjust certain settings of the chair and to facilitate recline or “tilt” of the chair superstructure, including the seat and back of the chair. This basic chair configuration allows users to change their sitting position in the chair as desired, such that fatigue may be minimized during long sitting periods.
In recent years, chair designs have implemented a feature where a chair back and seat both move simultaneously during a tilting or rearwardly reclining movement of the chair back. The chair seat may also tilt in this process or may be displaced otherwise relative to the chair base. The combined movement of the chair back and seat in these designs results in some level of improvement for the occupant through a range of tilting motions over a conventional “static” chair without coordinated back and seat movement.
For enhanced comfort, the coordinated movement of the chair back and chair seat should ideally account of the user's physique. The user's motion, when reclining his upper body relative to his thighs, may involve a rotation about his hip joints. It is desirable to support the user in this process.
Various configurations may be realized to implement such a coordinated movement of the chair back and chair seat. For illustration, the seat back may be articulated to an arm rest support or to a base at a location forward from the chair back. In order to implement a desired reclining or tilting movement of the chair back, guide elements have been provided on a rear side of the chair back. For illustration, a guide track may be formed on a rear side of the chair back, and a follower provided on a member which extends from the chair seat to the rear side of the chair back may be moved along the guide track as the chair seat moves, thereby causing the chair back to tilt. Providing such a member which extends from the chair seat to and along the rear side of the chair back may be undesirable for a variety of reasons, including the restrictions imposed on chair design or similar.
There is a need in the art for a tilt mechanism and chair which provides good support to the user during a reclining motion. There is a need in the art for such a tilt mechanism and chair which obviates the need for elements extending on the rear side of the chair back and across a significant portion of the chair back.